Positive Pressure Conveying System Supplier: Site Air Checks Before Quotation
Before a positive pressure conveying system supplier can assess an existing site air supply, identify the proposed air source, the connection point, pressure and flow under the relevant operating load, and the equipment included in each supplier’s scope. A compressor nameplate or a pressure reading taken while the plant is idle does not establish the air available to a conveying line.
Some arrangements use a dedicated blower; others require compressed air from a specified source. Clarify that choice first with the positive pressure conveying system supplier. This guide covers site air inputs for a quotation, rather than a general pressure-versus-vacuum comparison or a standard compressor-sizing rule.
First separate conveying air from auxiliary air
Ask which device generates the conveying airflow and which services operate valves, instruments or filter cleaning. Those duties may have different pressure, quality and consumption requirements. A connection marked “compressed air” on a layout is not a complete utility schedule.
For a dedicated blower arrangement, the quotation should define the blower duty, motor supply, inlet conditions and discharge connection as applicable. For a plant-air arrangement, define the purchaser’s delivery point and the conditions that must be available there. Do not assume that an existing plant header can support conveying simply because it already operates pneumatic actuators.
Use a site air record with named measurement points
Prepare the following original input sheet for the site utility owner and conveying supplier. Record observations and their operating context; leave unmeasured values open rather than filling them with assumed factory capabilities.
| Input | What to record | What the quotation should resolve |
|---|---|---|
| Air-source arrangement | Dedicated blower, dedicated compressor or shared plant header; proposed connection point | Who supplies the air source, treatment, storage and distribution connection |
| Pressure at the delivery point | Measured pressure with unit, gauge/absolute basis, location and operating state | Required range at the agreed boundary under the applicable duty |
| Flow and its reference basis | Measured or documented flow, meter location, actual or reference-volume basis and stated reference conditions | Comparable supply and demand figures using an agreed basis |
| Concurrent demand | Other users operating during the measurement and the expected conveying schedule | Whether the shared supply can support the proposed coincident load |
| Distribution and treatment | Route from source, restrictions, filters, dryers, regulators and their condition | Which pressure losses and treatment components lie within each scope |
| Air quality and environment | Application requirements and available evidence for relevant contaminants, moisture and temperature | Required treatment and verification for the actual material and product-contact duty |
Measurement work should be planned with the site’s responsible personnel using suitable instruments and approved connection points. The input sheet requests evidence; it is not an instruction to open or modify a pressurized system.
Measure the pressure that the conveying connection actually sees
Identify readings at the air-source outlet and at the agreed equipment connection. State whether the line is idle, starting, conveying or operating alongside other users. Record how the condition changes during the relevant duty instead of reporting only a single convenient gauge value.
A distribution restriction can make the connection condition different from the source condition. Treatment components and regulators also belong in the review. The supplier should distinguish a required delivery condition from a measured site condition and explain any unresolved gap before committing the scope.
For the broader equipment boundaries, see the pneumatic conveying component guide. The air source, feed device, pipeline and receiving arrangement must be assessed together; a site reading cannot determine the entire system design.
Do not compare flow numbers with different reference conditions
Write the unit and basis beside every flow figure. An actual volumetric flow and a flow expressed at stated reference conditions are different descriptions. “Normal” or “standard” needs an explicit definition when numbers from different documents are compared.
Record the relevant pressure and temperature basis and ask the equipment supplier to reconcile the figures. A motor rating, pipe diameter or receiver-tank volume is not a substitute for an air-delivery record. Where only estimated demand exists, identify the estimate and its assumptions.
For intermittent equipment, include the operating sequence and concurrent demand. Separate peak requirements, average consumption and the period over which they are assessed. Do not apply an average consumption figure to a peak event without confirming how the source and storage arrangement responds.
Video: where the air supply fits into a positive pressure line
This UPFLOW animation shows a general positive pressure dilute-phase conveying arrangement. It explains equipment relationships; it is not a site air measurement, a compressor duty test or proof of a particular conveying capacity.
Use a real integrated project to check the supply boundary
The published Egypt cement unloading and pneumatic conveying project describes an integrated scope including unloading, feeding, conveying, receiving and electrical control. It is relevant when checking the interfaces that must be covered by an enquiry.
The public case does not disclose the site’s air-pressure or flow measurements. It therefore cannot supply missing utility values for another plant. Where bulk bags are the source, review the ton bag unloading system interface as part of that same scope, and confirm the actual feed and isolation arrangement with the conveying designer.
What a supplier should return with the quotation
Request a utility schedule with the connection location, required operating conditions, consumption basis and customer-supplied items. Ask for a list of assumptions, exclusions and remaining verification steps. Distinguish conveying air from auxiliary services so that valves or cleaning functions are not omitted.
Agree who is responsible for confirming existing supply capacity, adding or modifying distribution equipment, supplying treatment, and demonstrating the integrated sequence. The aim is a comparable scope with a clear next action for each unknown input.
Frequently asked questions
Can the existing compressor supply the conveying system?
That depends on the selected conveying arrangement, available delivery conditions and concurrent plant demand. Provide the site records and have the utility owner and conveying supplier confirm suitability for the proposed duty.
Does a high header pressure prove that enough air is available?
No. Pressure, available flow, distribution losses and operating sequence need to be considered together. The important condition is the agreed supply boundary during the required duty.
What should I send before requesting a quotation?
Send the material data, route and receiving duty together with this site air sheet. The pneumatic conveying RFQ datasheet organizes the wider inputs. Then contact UPFLOW to review the proposed system and utility boundary.